Loss of independence, cognitive decline, and difficulties in everyday function are areas of great concern for older adults and their families, especially for fear of their signaling cognitive impairment related to Alzheimer?s disease and AD-related dementia. From a public health perspective, successful efforts that enable older adults to age within their homes, as compared to nursing homes, will save an estimated $80 billion dollars per year. Cognitive training is one low cost, noninvasive training intervention that has repeatedly demonstrated reliable transfer effects to maintained cognition, everyday function, health, and most recently, a 29% reduction in incident dementia, including Alzheimer?s disease. Importantly, many of these everyday function effects are maintained across five to ten years including: maintained driving mobility, 50% reduction in at-fault vehicle crashes, and maintained Instrumental Activities of Daily Living (IADL). Although clearly an important and effective intervention, the moderators and mechanisms underlying this program are unknown. Our overall objective in this planning grant is to lay the conceptual and methodological foundation to explore cognitive, psychosocial, lifestyle behaviors, biomarker, and neural mechanisms of two forms of conceptually driven cognitive training, with the long-term goal of forestalling, and perhaps even preventing, progression to Alzheimer?s disease. Additionally, we will examine how cognitive and psychosocial factors within daily life account for the transfer of cognitive training to everyday function. We will use a factorial design to randomize adults ages 45-90 to 10, 20, 30, or 40 hours of two forms of cognitive training, a combined training, or an active control condition. This study will allow us to test the feasibility of our enrollment, assessment and training protocols for a future multisite clinical trial. This exploratory study is the first of its kind and will be used to provide important data relevant to a future larger randomized controlled trial examining mediators of cognitive training in a representative sample of adults. This information will assist in the future development of more effective home- and community-based interventions that maintain everyday function and prevent or forestall cognitive impairment associated with Alzheimer?s disease and AD-related dementia.